Incombustible wall panel joint



Jan. 22, 1963 J. T. GARTRELL 3,074,123

INcoMBUsTIBLE WALL PANEL JOINT Filed Nov. 4, 1959 5 Sheets-Sheet 1 LNVNT R Jan. 22, 1963 J. T. GARTRELL 3,074,123

INCOMBUSTIBLE WALL PANEL JOINT Filed Nov. 4, 1959 5 Sheets-Sheet 2 AFroRNE-Ys.

Jan. 22, 1963 J. T. GARTRELL. 3,074,123

INCOMBUSTIBLE WALL PANEL JOINT 3 Sheets-Sheet 5 Filed Nov. 4, 1959' ATTORNEYS 3,074,123 INCMBUSTIBLE WALL PANEL .IOIN'I' John T. Gartrell, Donglassville, Pa., assigner to Birdsboro Corporation, Birdsb-oro, Pa., a corporation of Penn- Sylvania Filed Nov. 4, 1959, Ser. No. 850,855 1 Claim. (Cl. 2.0-4)

The present invention relates to incombustible Wall panels for buildings and the like.

A purpose of the invention is to obtain improved tire resistance in joints between one incombustible wall panel and another.

A further purpose is to more rapidly and conveniently make a joint between abutting incombustible wall panels.

A further purpose is to make a stronger joint in incombustible wall panels.

A further purpose is to render a joint in incombustible wall panels more adaptable to the particular conditions, so that it can be established by nails, screws, drive screws, and metallic connectors, without, however, destroying the tire resistance.

Further purposes appear in the specification and in the claim.

In the drawings I have chosen to illustrate a few only of the numerous embodiments in which the invention may appear, selecting the forms shown from the standpoint of convenience in illustration, satisfactory operation and clear demonstration of the principles involved.

FIGURE 1 is a side illustration of an incombustible wall of the invention.

FIGURE 2 is an end illustration of one of the wall panels of FIGURE 1 to enlarged scale.

FIGURE 3 is an enlarged fragmentary section of the wall of FIGURE l on the line 3--3. l

FIGURE 4 is a fragmentary perspective of the end of one of the wall panels, omitting the spline.

FIGURES 5, 6 and 7 are fragmentary perspectives of splines used in making the joint of FIGURES l to 4 inelusive.

FIGURES 8, 9 and 10 are sections similar to FIGURE 3 showing variations.

Describing in illustration but not in limitation and referring to the drawings:

'Ihere is a considerable need in building construction -for improved incombustible or tire walls which will serve as interior walls and in some cases as exterior walls of buildings and the like. It is important in such construction that the walls be fire resistant for a predetermined time, in some cases for as long as eight hours.

Diiculty has been encountered in making joints in abutting fire wall panels without impairing the lire resistance. It is also important that such walls withstand smoke, and have adequately 10W heat transmission, and the like.

The present invention is concerned with an improved joint between abutting ends of tire wall panels.

The joint of the present invention is quickly and easily made, under very favorable conditions of installation, and yet it does not impair the tire resistance of the wall, and leaves the wall adequatelyV resistant to heat transmission, sound transmission and the like.

The wall of FIGURE l consists of three panels 20, 21 and 22 each of which consists of an incombustible board 23 on each side suitably of cement asbestos board of Well known character. The cement asbestos board is joined to a core 24 of incombustible material.

The core of the panel is desirably for example made from expanded perlite plus fibrous material.

By perlite it is intended to indicate a natural volcanic glass which contains a small amount of water in its structure. When perlite is heated to an elevated temperature,

such as 1700" F., a cellular annealed structure is formed with closed cells and this is available on the market. This expanded perlite is of such low density that it usually lloats on water.

The expanded perlite is preferably of line size, suitably through 20 mesh and more desirably through 30 mesh per linear inch.

The expanded perlite is suitably formed into a core material by mixing with from 30 to 90% by weight of a 4iibrous material such as glass wool, rock wool, slag wool, asbestos or fibrous wollastonite. In the preferred embodiment about 30% lby Weightv `of the brous material is used.

The mixture desirably also will incorporate a small amount, of the order of il%, of a size or binder such as rosin size.

In some cases much less desirably organic fiber such as sugar cane fiber, cotton fiber, or the like, will be incorporated instead of inorganic fiber, and it does not seriously interfere with the hre resistance because it is very slow burning.

In some cases Portland cement is used as a binder of perlite, in the proportions of 1 cement to 4 or 8 of perlite by volume.

The core material will have a density of the order of 11 pounds per cubic foot, a linear expansion between 50% and 97% relative humidity lengthwise of 0.2% vand crosswise of 0.09%, a compression resistance of 175 p.s.i., and a sound transmission average attenua-tion of 38.1 decibels.

The thermal conductivity (k factor, that is, rate of heat ilow through l inch thickness of a single kind of material), is 0.34 B.t.u./sq. ft./hr./ F. The thermal expansion from 0 to 75 F. is 0.145% increase.

The water absorption in percent by volume on 2 hours total immersion is 0.60%.

The heat transmission Value (U, that is, the rate of heat flow -through a combination of materials forming the wall in la total thickness of 2% incheswith a core thickness of 2 inches) is 0.148 B.t.u./sq. ft./hr./ F.

The incombustible boards 23 are joined to the core at 2S by suitable adhesive such as chlorinated rubber and the core is provided in two sheets suitably joined as by the same adhesive a-t 26.

At the end of each one of the panels, there is la slot 27 which abuts a similar slot in the abutting panel so as to receive an incombustible spline 28 suitably made of cement asbestos board.

Each of the slots 27 extends across the full width of the core material 24 'at the outer end to provide parallel sides 30, and when i-t has extended back for a short distance, suitably an inch or more, the slot has converging substantially equilateral sides 3l on the core Z4 which extend at an acute angle with respect to each other, and before the two converging sides join proximate to a transverse midpoint of the core, the slot ends in flat base 32.

The spline 28 is generally of diamond cross section and has parallel sides 33 at the center which engage the boardsV at 30, and then converging porti-ons 3'5 which engage the converging Walls 31 of the slot and a tlattened end 36 which seats against the flattened end 32 of the slot.

Adhesive is applied to the outer surfaces of the spline -at 33, 35 and 36. There is anelongated line of adhesive Contact with 4the walls of the slot 31 as compared with a rectangular slot all of whose sides are parallel so that greatly increased bond is obtained when one panel and the next is joined. The adhesive used in chlorinated rubber.

When the spline is properly seated in 'the slots so that the adhesive is in tlrrn engagement, the spline is anchored and 4the wall panels are locked in place by metallic fasteners which may be nails 37 driven in through the boards 23 from each sider of each panel as in FIGURE 3,

l requiring cutting on the job.

care being taken that the nails are not long enough to bring their points close to one another, the nails being substantially shorter than half the thickness of the wall panel, so as to leave space at 3S between the inner ends as 'shown in FIGURE 3 which is at least a half, inch and prelferably one inch between Ythe adjoining points of the nai s.

The spline has at the center onveach side a slot di? which suitably runs the full length from top .to bottom and assists in lining up the center of the spline with ythe joint 41 between the panels, thus aiding the Workman when bringing the panels together in knowing when the spline is fully seated.

A The spline is conveniently made in several short pieces 28', 282 and 283 as shown in FIGURES 5 -to7, Vthe spline ZSbeing suitably at the top and having a bottom groove 42 across the middle of the lower end` The next spline section 282 has a transverse tongue 43 at the top which interlocks with the groove 42, anda'transverse groove 44 at the bottom which interlocks with a transverse tongue 45 -on 'thettop of the spline section/283.

p In somec-ases it is preferred to secure'thepanels to the spline by wood'scr'ews 3-7' enteringfrom each side of each panel as shown in 'FEGURE 8, being careiulthat the wood screwsdo not intersect and of coursel extend less than half 'across the'thickness preferably leaving at least a half `inch andpreferably one inch between their inner ends.

In some cases it is preferred to usevdrive screws, and in FIGURE 9 I show drive screws 372 extending on one Vside from eachrof the panels less than halt, of the distance .acrossjthe thickness (desirably with a space of `one half 4inch and preferably one inch from the inner end of the .screws von Vthe other side), at the other side screws .373 -anchor a-metallie sealing strip `which extends across the 'jointbetween the panels, land runs lengthwise of the joint.

'In FIGURE 10 drive screws ,372 enter into the spline from each side of eachipanel to a distance less than'half Having thus described my invention what I claim as new and desire to secure 'by Letters Patent is:

In an incombustible wall panel joint, a first Wall panel of incombus'tible material having incombustible side boards having a high resistance to heat transmission extending in at planes-tand an incombustible core joined to the side boards, there being la slot at the end of the rst wall panel which in cross section extends in major width directly along the inside of the side boards from said end and thence rextends into the core and has opposite converging substantially -eqnilateral sides extending inwardly of theV panel ,at an :acute angle with respect to each other and terminating proximate to a 'transverse midpoint of ofthe thickness, with a clearanceo'fat least onehalf inch, Y

and preferably one inch between inner ends, and then an additional sealing strip 375 and 376 on the Kopposite sides is held by screws 37"! which extend in oni;` a relatively short distance compared to the drive-screws 372.

Allk ofthe metallic fastenings are suitably of steel .or

stainlesssteeL I Y It will be evident that the groove for the ,spline will suitably be prefabricated at the factory and the spline will be prefabricated so that the joint can be made without if the height of the panel is cut down a similar height can be cut off the spline to make it conform with the height of the panel.

In view of my invention anddisclosure, variations and modilicationsfto meet individual whim or particular needV will'doubtless become evident to others skilled in the art,

pto obtain all or part of the benefits of my invention with- Vout 'copying' the structure shown, and L'therefore, claim all such insofar as they fall within the reasonable spirit and scope of my claim. Y

It will also be evident thaty the core with a flat base, said equilatertal sides and base being formed by the core, a second wall panel abutting the iirst adjacent to said slot, composed of Aincombustible material and having incombustible second side boards having a high resistance to heat transmission extending in at planes'at the sides land an incombustible second core Vjoined to the side 'boards of said second panel between said second side boards, there being a Vslot in said second panel at said abutting end thereof which in cross section Vextends in'major width directly along the vinsides `of said second side boards from said `end of `the second panel and thence extends `intosaid second core and has opposite converging substantially equilateral'sides extending inwardly ofthe second panel Vat anacute angle with respect to each other and terminating proximate to a transverse midpoint of the second core with a flat base, said equilateral sides and base of said slot Yin saidsecond panel being 'formed by said second core, a splineof incombustible material having a high resistance to heat transmission and in cross section conforming Vto the cross Vsection of said'slots and thus having opposedparalleldlat sides in abutting relationship with said'sideboards, pairs of opposed sides abutting the corresponding opposite'sides of the slots of said panels, and'ilat end faces abutting lthe icorresponding ilat bases formed by said core, zand'metallic ,fastenings extending through each side boardmofthe'wall panels into the spline for a distance less thanhalf the thickness of the spline.

References Cited in the tile of this :patent UNITED STATES PATEN'IS 

